Negligibility of Intraparticle Temperature Gradients

Apply the three criteria 7.23,7.24 and 7.28 to the data given in example 9.10. 

The reaction order n = Vi and hence the criteria for isothermal operation are 

The actual value of was 0.051. Thus according to criteria 7.23 and 7.28 the catalyst can be regarded isothermal. Even the high tj criterion is as good as fulfilled. Since we operate in the intermediate j/ region, the relative error introduced by assuming isothermal operation must be much smaller than 10 %. Actually it is 2 %, as was calculated in Example 9.10. 

According to Mears criterion the catalyst cannot be regarded as being isothermal because = 0.051 0.025. This illustrates that Mears criterion is too stringent. 

13 Effectiveness Factors Larger than one for Langmuir-Hinshelwood Kinetics 

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